How Many Capillaries? The aorta has an inside Part A diameter of approximately 2.1 cm, compared to that of a capillary, which is about 1.0 x 10 s m (10 am) In addition, the average speed of flow is approximately 1.0 m/s in the aorta and 0.3 mm/s in a capillary Assuming that all the blood that flows through the aorta also flows through the capillaries, how many capilaries does the circulatory system have? Express your answer using two significant figures. Submit Reauest Answe Solution let d1 = 2.1 cm = 0.021 m v1 = 1 m/s d2 = 10 micro m = 10*10^-6 m v2 = 0.3 mm/s = 0.3*10^-3 m/s volume flow rate through arota = volume flow rate through capillaries area of arota*speed = area of capallaries*speed A1*v1 = n*A2*v2 (pi*d1^2/4)*v1 = n*(pi*d2^2/4)*v2 ==> n = (d1/d2)^2*(v1/v2) = (0.021/10^-5)^2*(1/(0.3*10^-3)) = 1.5*10^10 <<<<<<----------------Answer .

1. How Many Capillaries? The aorta has an inside Part A diameter of approximately 2.1 cm,
compared to that of a capillary, which is about 1.0 x 10 s m (10 am) In addition, the average
speed of flow is approximately 1.0 m/s in the aorta and 0.3 mm/s in a capillary Assuming that all
the blood that flows through the aorta also flows through the capillaries, how many capilaries
does the circulatory system have? Express your answer using two significant figures. Submit
Reauest Answe
Solution
let
d1 = 2.1 cm
= 0.021 m
v1 = 1 m/s
d2 = 10 micro m
= 10*10^-6 m
v2 = 0.3 mm/s
= 0.3*10^-3 m/s
volume flow rate through arota = volume flow rate through capillaries
area of arota*speed = area of capallaries*speed
A1*v1 = n*A2*v2
(pi*d1^2/4)*v1 = n*(pi*d2^2/4)*v2
==> n = (d1/d2)^2*(v1/v2)
= (0.021/10^-5)^2*(1/(0.3*10^-3))

2. = 1.5*10^10 <<<<<<----------------Answer